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danihxh
08-12-2010, 07:20 AM
Hello everyone!

I’m doing a research project about Hydrogen and its applications, especially the energetic ones, and I’m planning to build a Dry Cell due to demonstrate some of them, but I’ve a few questions…

First of all you should know that I want to build a cell to be powered with about 12v, so that I can use it both in a car (connected to its battery) or connected to a PWM circuit with a AC/DC converter. I want to be able to regulate the gas production by limiting the current that goes through the cell but not changing the voltage so that I can use the cell for different aplications that require differents amounts of gas: a car (if it’s possible and works well), a welding torch (so that I’ll need a flashback arrestor and all that stuff)…

Well, so now the questions… The first one is that what would be the best plate configuration to achieve a good production? I’ve read that a Dry Cell is better than a Bath Cell because they don’t have leakage due to the edges are not in the solution and about the configuration I’ve to achieve about 1,4v - 2v per gap, so I think the best configuration would be -NNNNN+, so what do you thing about that? And how many blocks like that I should put together to achieve enough production? Maybe -NNNNN+NNNNN-NNNNN+NNNNN- will be enough?

Oh, I nearly forgotten… My plates are made of steel and measure 10cm x 15cm x 1mm.

Now my second question. This is about how to build the cell. I’ve seen that a lot of Dry Cells are built in a similar way: The plates have a soft PVC or polycarbonate separator or something like that between them and a hole in the middle to allow the water flow; the two closing covers are made of methacrylate and one has a water input in the bottom and the other has a gas output in the top... and all that is packed together with long screws. So I have two different questions about all this: First, I want to know what would be better to use: soft PVC or polycarbonate; and the second one is if the following design is better than the one I’ve just explained.

http://img180.imageshack.us/img180/2742/57267216.png

And the last two questions: How can I measure the HHO production? And is there anybody who can help me with the circuit? I don’t know how to start with that… I’ve seen Patrick J. Kelly’s circuit ant it seems very confusing.

Well… I hope anyone can help me with that. Thanks in advance :D

lhazleton
08-12-2010, 02:53 PM
Welcome to the forum. The design you have pictured above is a wet-cell reactor. Not worth the trouble.
You need to do a bit of research, as the answers to all of your questions are already covered numerous times in here.
We're all here to help, but really don't like repeating ourselves, answering the same questions over and over again.
The dry-cell reactor setup you mentioned sounds good. Basically what most of us use.
Good luck & keep us posted.

myoldyourgold
08-12-2010, 04:47 PM
Lee, this could be a dry-cell if the edges and the bottom are sealed. That is a trick in its self and has been tried many times and found they leak. The other problem, if this is a dry-cell, is that the only way to keep the cells balanced is by flooding thus current leakage at the top. As the water gets used up the fill system shown would not put the same amount of water in each cell creating heat, and uneven production in the cells. Your advise of doing more research is right on.

lhazleton
08-12-2010, 07:50 PM
Carter,
There is a 'gas reservoir', consisting of the top of the container, and you can clearly see that the plates sit in an open bath. There's even a friggin' sensor to keep the e/lyte from filling more than half way. :rolleyes:
What a waste of plate area!
All I see is an inefficient wet cell that'll leak both gas and e/lyte.

myoldyourgold
08-12-2010, 08:36 PM
You are right Lee, based on the drawing it is ridicules and a poor open bath reactor. I thought sense he mentioned a dry cell reactor it was just drawn poorly, and wanted to point out that even if it was a "dry-cell" it was still a piece of fecal mater. Is that clearer? :D

danihxh
08-12-2010, 10:04 PM
Sorry, I couldn't post a photo before... The drawing is not very good.

http://img185.imageshack.us/img185/2022/57213016.png

The idea of that cell is good if it could work ideally, but it doesn’t. The case has some kind of guides cut on it where all the plates can be fitted in so they stay separated and no edges are in contact with the solution, so no leakages either, but the problem is the water distribution since, despite the water should come from the thin top tube which has a few holes drilled on the bottom, won’t be regular, so some cells will have more water than others, resulting on a possible water overflow in some of them and a drain of others.

Well, I certainly won’t build a cell like that.

myoldyourgold
08-12-2010, 10:20 PM
That is a Bob Boyce 101 plate case. If I remember. You are right it is sealed on the edges and bottom. They have been found to leak and are very expensive to build with yet no real evidence of any major gains when used in brute force mode. With the required electronics results are disputed. I suggest you use the KISS principle and use what is commonly called a Taro or Dry-cell. This to if my memory serves me was also started by Bob. Makes no difference who but it seams to be working for most. You will find lots of information on these reactors on this and other forums. Do some research and you will be happy you did. Ignore some of our remarks unless you want to join in on the fun. :)

danihxh
08-12-2010, 10:55 PM
As you told me I’ve done some research so this is what I’ve understood, but I still has a few questions…

Well… As it’s very important to prevent holes and edges in the solution, I think the best way to pack all that stuff is to use 3mm thick polycarbonate (it’s softer than soft PVC, so it acts more like rubber) to separate the plates and fixed all that with thin nylon screws or metal ones with some insulating cover (that will act only as guide) and some metal screws pressing all together between the end covers. It’s Ok to put 3mm separation?

Each plate should have 2 holes: one at the top to allow the gas circulation (which doesn’t produce leakage since it’s not in the solution) and another one in the bottom which will allow the water circulation and, unfortunately, will produce leakage. I’ve read that people have tried many different systems to insulate these edges, but that most of them doesn’t work too long and the ones that do are too expensive… So I’ve been thinking about that and well… the only thing I can think of is to put them in alternative sides… What do you think about that? Any other idea?

Another important thing to keep in mind is that I should have an easy way to connect the plates in different ways because I think I will have to do a bit testing an measurements to choose a good plate configuration, so I thing that this can be done by making a small cut in alternative corners of the plates, so that I can attach a faston there.

And now I have a question about voltage distribution and neutrals… I’ve read a lot of posts about that but it doesn’t help… I thought before to use +NNNNN- blocks, so each gap gets about 2v (12v total), but some people says that using 3 or 4 neutrals is better and other say that it’s better to put the cells in series but, theoretically, it should be the same than using 5 neutrals, because each gap gets 2v… Can anyone help me with that? And one more thing: it is supposed that the gas production take place between the plates and that these are only used to ‘split’ the voltage so we have about 2v per gap so what if I use plates thinner than 1mm, about a half or less? Wouldn’t it be a better production since less current is getting lost in the plates?

As soon as I build my cell I’ll start to measure productions with different connections to find out which one is better and I think I will go to buy all I need this Saturday, so please, help me decide the gap width and the plates measures… I thought about a 3mm gap and 10cm x 15cm x 1mm plates would be Ok, but this will result on only about 100cm2 active surface per plate side. Will this be enough if I have about 40 plates to produce enough gas for a welding torch or for a car? And is Ok to use 1mm thick plates or is better to use thinner ones as I suggested before?

Sorry for writing so much, but I couldn’t find anything about that in other posts.

Thanks in advance!

lhazleton
08-12-2010, 10:57 PM
You are right Lee, :D


Carter,
Have you EVER known me to be WRONG??????????????????:confused::confused: LOL

danihxh
08-12-2010, 10:59 PM
I've changed my mind about the gap... 2mm will be Ok.

myoldyourgold
08-12-2010, 11:40 PM
As you told me I’ve done some research so this is what I’ve understood, but I still has a few questions…

Well… As it’s very important to prevent holes and edges in the solution, I think the best way to pack all that stuff is to use 3mm thick polycarbonate (it’s softer than soft PVC, so it acts more like rubber) to separate the plates and fixed all that with thin nylon screws or metal ones with some insulating cover (that will act only as guide) and some metal screws pressing all together between the end covers. It’s Ok to put 3mm separation?

Each plate should have 2 holes: one at the top to allow the gas circulation (which doesn’t produce leakage since it’s not in the solution) and another one in the bottom which will allow the water circulation and, unfortunately, will produce leakage. I’ve read that people have tried many different systems to insulate these edges, but that most of them doesn’t work too long and the ones that do are too expensive… So I’ve been thinking about that and well… the only thing I can think of is to put them in alternative sides… What do you think about that? Any other idea?

Another important thing to keep in mind is that I should have an easy way to connect the plates in different ways because I think I will have to do a bit testing an measurements to choose a good plate configuration, so I thing that this can be done by making a small cut in alternative corners of the plates, so that I can attach a faston there.

And now I have a question about voltage distribution and neutrals… I’ve read a lot of posts about that but it doesn’t help… I thought before to use +NNNNN- blocks, so each gap gets about 2v (12v total), but some people says that using 3 or 4 neutrals is better and other say that it’s better to put the cells in series but, theoretically, it should be the same than using 5 neutrals, because each gap gets 2v… Can anyone help me with that? And one more thing: it is supposed that the gas production take place between the plates and that these are only used to ‘split’ the voltage so we have about 2v per gap so what if I use plates thinner than 1mm, about a half or less? Wouldn’t it be a better production since less current is getting lost in the plates?

As soon as I build my cell I’ll start to measure productions with different connections to find out which one is better and I think I will go to buy all I need this Saturday, so please, help me decide the gap width and the plates measures… I thought about a 3mm gap and 10cm x 15cm x 1mm plates would be Ok, but this will result on only about 100cm2 active surface per plate side. Will this be enough if I have about 40 plates to produce enough gas for a welding torch or for a car? And is Ok to use 1mm thick plates or is better to use thinner ones as I suggested before?

Sorry for writing so much, but I couldn’t find anything about that in other posts.

Thanks in advance!




Most of your questions have been answered before. But I will start you on your way. You have proposed to make a reactor the is proximately 4 X 6 (10 X 15cm) inches and will have a gap of just over 1/16" (2mm) between plates. So far you have made good choices. The best configuration is going to depend on if it is going to be running in a car at 13.8 to 14.2 volts or just on a battery at maximum 12.5 volts and dropping quickly. In a car I suggest 6 bi polar (neutrals) and on a battery alone 5 bi polar plates. How many stacks you will need of these is going to require a lot more information and is related to how much gas you are trying to make, size of engine/alternator etc. Do some more research use the search feature and you should find all the answers you need. Gaskets are something you also need to research and how a dry-cell is assembled. Good luck and Welcome the forum.


Carter,
Have you EVER known me to be WRONG??????????????????

Lee the last time I made a mistake was before you were born. LOL :D

danihxh
08-13-2010, 07:42 AM
Ok, I've read about the gaskets... Thanks for the info, I didn't know that word.

Well, I think I will use EPDM gaskets since it's easy to obtain and work with that rather than with polycarbonate and they will be about 3mm thick due to it's a soft material and I think if I press the end covers enought I should obtain a gap of about 2mm which is what I want.

I will also try what I said before about alternating the side of the water holes and I will look for some plates a little thinner than 1mm and maybe a bit bigger than 10cm x 15cm. About the bi polars I will start with 5 and then try different configurations.

astrocady
08-13-2010, 12:16 PM
if I use plates thinner than 1mm, about a half or less? Wouldn’t it be a better production since less current is getting lost in the plates?

Stainless Steel is a poor conductor. The thinner your plates, the more resistance they have, which means wasted energy (heat) just to overcome that resistance. This applies mainly (only?) to the plates you connect to the power supply, not the bipolar plates.

Steve

danihxh
08-19-2010, 04:28 PM
What can I use as a power supply? I need something that can deliver about 40 amps, but I don’t want to buy an expensive bench power supply, so what do you think about using 2 ATX power supplies so that I can obtain up to 40 amps.

http://www.pccomponentes.com/b_move_fuente_alimentacion_500w.html

Using two of them I will have 12 volts at 56 amps (28 + 28) and I may use the rest of the connections for indicators or something.

One more question… I’ve seen a lot of different bubbler-deposit configurations: in some of them the water tank is used also as bubbler, some others have 3 or more different bottles/tanks (ones as bubblers, others as deposits…)… What do you recommend me? I thought doing something like that. Is it Ok?

http://img148.imageshack.us/img148/534/sinttuloxm.png

myoldyourgold
08-19-2010, 04:58 PM
Reverse your bubbler and reservoir. It should go Reactor, reservoir, bubbler. The reason for this is that the bubbler's two functions are to clean electrolyte from the gas and the other is to help prevent a flash back getting to the reservoir/reactor. The electrolyte is harmful in any volume to anything aluminum.